Figure CRF4.2 shows the average reading scores for this group and for year four students in Solomon Islands in previous PILNA cycles. The scores in 2021 were slightly lower than in 2018, but not by much. Overall, the average reading scores for year four students in 2015, 2018 and 2021 were similar. The standard deviation for the reading scores in 2021 was slightly higher than in 2015, and slightly lower than in 2018. This means that the spread of year four overall reading scores was wider in 2021 than in 2015 but narrower than the 2018 spread.

Standard deviation shows how close data points are to the average. A lower standard deviation means that data points are, overall, closer to the average; a higher standard deviation means that data points are, overall, further away from the average.